Hello.
With this thread I'm going to collect all KDE4 issues on PowerBooks:

Collisions with pbbuttonsd:

The powermanagement of KDE4 allows to configure modes for AC or battery power such as pbbuttonsd does. Is it advised to disable that and let pbbuttonsd do the job? So far I had no problems with KDE4 but I did not touch the KDE4 settings of this section.

New kmix has its own on screen display, so for volume I currently have both OSDs gtkpbbuttons and kmix. Not found yet how to disable kmix.

This actually is an issue already there with KDE3.5 and maybe rather about X: After kdm has come up, the LCDBRIGHTNESS always is at maximum, eventhough pbbuttonsd was not configured to:

Code:

# grep "LCD_Bright" /etc/pbbuttonsd.cnf
LCD_Brightness=50

This is also the case when the display resumes.

Then the display turns completely dark after idle timeout without pbbuttonsd:

Personally I would prefer keep using pbbuttonsd for power management control and stay with my carefully configured /etc/power/pmcs-pbbuttonsd and scripts (yes I made the book speak with my own speech-dispatcher scripts, going to publish of s.o. is interested).

In general even on the latest PowerBook G4 the new desktop effects and visualization is quite slow, but usable. Not sure if there are possible X improvements to be expected or if that graphics board (ATI Technologies Inc RV350 [Mobility Radeon 9600 M10]) is just at the limit of its capabilities.

I don't see how to disable KDE's powermanagement completely:
For now I just disabled the screen settings for all profiles, so KDE doesnt change LCD brightness anymore and lets pbbuttonsd do the job.
The powermanagement section in KDEs systemsettings is a bit confusing. For profiles there are 3 tabs on the right: actions, screen and cpu-stuff. Actions I disabled every event. On screen I disabled powermanagement. For CPU it actually does the same as other cpu frequency tools that is switching the cpu governor between powersave, performance and userspace. After a while I decided to use sys-power/powernowd and would like to stick to that for dynamic load depending switching. But I did not find out how to disable the KDE cpu settings completely or even delete the profiles._________________ppc:PowerBook5,8 15"(1440)-G4/1.67,2G | amd64:Acer Z5610 (Core2QuadQ8200),i5-3470,VMware VM @ i7-2620M | amd64-prefix:OpenSuse | Lila-Theme

just wanted to ask a related question : does kde´s power management ( or more specifically powerdevil ) even work for someone here in ppc world ?
Because it apparently doesn´t know how handle any event in my wife´s powerbook, at all. I mean, disconnect the power supply and it doesn´t know that it is sucking from battery f.ex.

In general even on the latest PowerBook G4 the new desktop effects and visualization is quite slow, but usable. Not sure if there are possible X improvements to be expected or if that graphics board (ATI Technologies Inc RV350 [Mobility Radeon 9600 M10]) is just at the limit of its capabilities.

For the record:
I am running KDE4 on a Mac Mini G4 1.4GHz and can say that the damn screen candy of KDE4 sucks big time on this machine. I had to disable all of it in order to have any responsive desktop at all. Graphics card is a RV280 (Radeon 9200).

I noticed that the slowness is based somewhere else. The process plasma-desktop keeps always around 50% CPU load in top. As fallback I'm back on fluxbox for a while, using KDE applications which run lot faster there.
Before opening a new thread here about that CPU usage, I will try from scratch with a clean xorg.conf to figure out the problem._________________ppc:PowerBook5,8 15"(1440)-G4/1.67,2G | amd64:Acer Z5610 (Core2QuadQ8200),i5-3470,VMware VM @ i7-2620M | amd64-prefix:OpenSuse | Lila-Theme

The "problem" is simple i think : kde4 is very resource hungry, specially if one enables all the fancy stuff or indexing.
I mean, some of your problems should go away if you disable the effects (in case you have them enabled) and you remove all your plasmoids f.ex. At least it made a difference here.

i didnt read the other thread carefully enough, you already mentioned there you have plasmoids and effects turned off.
In that case, yeah, looks like a bug or configuration issue to me too. Any chance you running xorg-1.8 & kms ? because i had some serious X performance troubles with this combination in my pb.